A four-year clinical trial found that taking vitamin D reduced cancer by 60 per cent, a drop so large — twice the impact on cancer attributed to smoking — it almost looks like a typographical error.

Their results are nothing short of astounding – a five-alarm blaze on the health front.

Vitamin D deficiency is showing up in so many illnesses that nearly all disease figures in Canada and the U.S. will need to be re-evaluated. As well as cancer, low vitamin D status is linked to a host of other serious ailments, including multiple sclerosis, juvenile diabetes, influenza, osteoporosis and bone fractures among the elderly.

Researchers at the University of California, San Diego, for example, suggested in the March 2007 issue of the American Journal of Preventive Medicine that taking 2,000 international units of vitamin D daily along with 10 to 15 minutes in the sun and a healthy diet could reduce the incidence of colorectal cancer by two-thirds.

The same authors found that breast cancer rates were 50 per cent lower in people with high levels of vitamin D in their blood, and suggested that the average person could maintain those levels by taking 2,000 IU of vitamin D daily and spending 10 to 15 minutes in the sun.

The main way humans achieve healthy levels of vitamin D isn’t through diet but through sun exposure.

People make vitamin D whenever naked skin is exposed to bright sunshine but in northern latitudes most vitamin D may be depleted by mid-winter.

Warned that strong sunshine causes sunburn and skin cancer most people spend little time outdoors or cover their skin with sunscreen.

Modern humans may have only about one-quarter to one-third of the vitamin that humans would have in the wild.

Anyone practising sun avoidance has traded the benefit of a reduced risk of skin cancer — which is easy to detect and treat and seldom fatal — for an increased risk of the scary, high-body-count cancers, such as breast, prostate and colon, that appear linked to vitamin D shortages.

The sun advice has been misguided information “of just breathtaking proportions,” said John Cannell, head of the Vitamin D Council, a non-profit, California-based organization.

“Fifteen hundred Americans die every year from [skin cancers]. Fifteen hundred Americans die every day from the serious cancers.”

Those with very dark skins, whose ancestors originated in tropical, light-rich environments, have pigmentation that filters out more of the sunshine responsible for vitamin D; in northern latitudes, they need more sun exposure — often 10 times as much — to produce the same amount of the vitamin as whites.

Smoking and some pollutants, such as benzene and asbestos, irrefutably cause many cancers. But it may be that cancers and other disorders in rich countries aren’t caused mainly by pollutants but by a vitamin deficiency known to be less acute or even non-existent in poor nations.

Vitamin D is a hot topic lately. Medical journals and newspapers are overflowing with the latest news on vitamin D, specifically vitamin D3 cholecalciferol, and the many ways it protects one’s health.

The American Cancer Society warns that more than 2,000 units vitamin D may be potentially dangerous. Current recommendations are from 200 to 600 units depending on a person’s age. New research and recent recommendations from are encouraging an increase to 1,000 units.